This invention relates generally to an adhesive applicator, and more particularly to such an applicator which makes use of a roller of the intaglio type for effecting continuous application of spots of adhesive onto a moving web.
Various approaches have in the past been used in applying spots of adhesive onto moving webs such as paper to serve as a securing means in lieu of glue streams. Among these are such devices wherein resilient pads are wetted for the spot application of glue as the pads contact an adhesive transfer roll. Also, protruding pads on a web backup roll of another device effects glue spot application as portions of the roll are made to thereby intermittently contact an applicator roll. Another approach taken in applying glue spots is with the use of a roller of the intaglio type having its cavities filled with adhesive by means of an adhesive fountain or glue pot. However, in each of these prior art developments as shown by U.S. Pat. Nos. 3,092,513 and 2,787,244, applicator and fountain rolls must be used or a glue fountain is required to carry out the spot glue application. More importantly, the speed capability of these devices are limited because of their inherent inability for adequately controlling the amount of spot glue during application. Moreover, these prior art devices are generally cumbersome and relatively complex because of the paricular techniques used in carrying out the spot glue applications.